package com.czk.model.facade;

public class Stereo {
    private Stereo(){}
    public static final Stereo stereo=new Stereo();
    public static Stereo getInstance(){
        return stereo;
    }
    public void up(){
        System.out.println("立体声音量调大");
    }
    public void down(){
        System.out.println("立体声下调");
    }
}
